Nanobiochar and Copper Oxide Nanoparticles Mixture Synergistically Increases Soil Nutrient Availability and Improves Wheat Production.

Recently, nanomaterials have received considerable attention in the agricultural sector, due to their distinctive characteristics such as small size, high surface area to volume ratio, and charged surface. These properties allow nanomaterials to be utilized as nanofertilizers, that can improve crop nutrient management and reduce environmental nutrient losses. However, after soil application, metallic nanoparticles have been shown to be toxic to soil biota and their associated ecosystem services. The organic nature of nanobiochar (nanoB) may help to overcome this toxicity while maintaining all the beneficial effects of nanomaterials. We aimed to synthesize nanoB from goat manure and utilize it with CuO nanoparticles (nanoCu) to influence soil microbes, nutrient content, and wheat productivity. An X-ray diffractogram (XRD) confirmed nanoB synthesis (crystal size = 20 nm). The XRD spectrum showed a distinct carbon peak at 2θ = 42.9°. Fourier-transform spectroscopy of nanoB's surface indicated the presence of C=O, C≡N-R, and C=C bonds, and other functional groups. The electron microscopic micrographs of nanoB showed cubical, pentagonal, needle, and spherical shapes. NanoB and nanoCu were applied alone and as a mixture at the rate of 1000 mg kg-1 soil, to pots where wheat crop was grown. NanoCu did not influence any soil or plant parameters except soil Cu content and plant Cu uptake. The soil and wheat Cu content in the nanoCu treatment were 146 and 91% higher, respectively, than in the control. NanoB increased microbial biomass N, mineral N, and plant available P by 57, 28, and 64%, respectively, compared to the control. The mixture of nanoB and nanoCu further increased these parameters, by 61, 18, and 38%, compared to nanoB or nanoCu alone. Consequently, wheat biological, grain yields, and N uptake were 35, 62 and 80% higher in the nanoB+nanoCu treatment compared to the control. NanoB further increased wheat Cu uptake by 37% in the nanoB+nanoCu treatment compared to the nanoCu alone. Hence, nanoB alone, or in a mixture with nanoCu, enhanced soil microbial activity, nutrient content, and wheat production. NanoB also increased wheat Cu uptake when mixed with nanoCu, a micronutrient essential for seed and chlorophyll production. Therefore, a mixture of nanobiochar and nanoCu would be recommended to farmers for improving their clayey loam soil quality and increasing Cu uptake and crop productivity in such agroecosystems.

Synthesis and characterization of porous reduced graphene oxide based geopolymeric membrane with titanium dioxide coating for forward osmosis application.

Forward Osmosis (FO) is a promising separation technology with a wide range of applications in water and wastewater treatment. FO membrane is the core of the forward osmosis process. Recently, the organic membrane has been widely used for forward osmosis applications even though inorganic membrane has excellent mechanical properties, decent chemical resistance, high durability, high porosity, and good hydrophilicity. Nevertheless, the utilization of inorganic membrane is hindered by the heat-intensive steps involved in its fabrication and the use of expensive source material. Geopolymerization provides a cost-effective technique for the preparation of inorganic membranes because of its sintering-free steps and utilization of fly ash as source material. Herein, we present a sintering-free, environmentally friendly, and cost-effective synthesis of geopolymeric membrane for application in forward osmosis. Fly ash was mixed with alkaline activator solution and porous reduced graphene oxide (PRGO) to prepare geopolymer slurry. The hydrogen peroxide and egg albumen were used as foaming agent and surfactant, while the membrane surface was coated with titanium dioxide to enhance the hydrophilicity of the membrane surface. The PRGO content improved the mechanical properties of the geopolymeric membrane. The average maximum flux recorded was 21 L/m2 h with geopolymer substrate having a pore size of 1.8 µm and hydrophilic coated layer pore size of 0.25 µm. The varying concentrations of PRGO control the substrate's mechanical properties and pore size, as well as provide new insights for future studies. These preliminary results show that low-cost geopolymer material is a promising candidate for FO membrane fabrication.

SELWAK: A Secure and Efficient Lightweight and Anonymous Authentication and Key Establishment Scheme for IoT Based Vehicular Ad hoc Networks.

In recent decades, Vehicular Ad Hoc Networks (VANET) have emerged as a promising field that provides real-time communication between vehicles for comfortable driving and human safety. However, the Internet of Vehicles (IoV) platform faces some serious problems in the deployment of robust authentication mechanisms in resource-constrained environments and directly affects the efficiency of existing VANET schemes. Moreover, the security of the information becomes a critical issue over an open wireless access medium. In this paper, an efficient and secure lightweight anonymous mutual authentication and key establishment (SELWAK) for IoT-based VANETs is proposed. The proposed scheme requires two types of mutual authentication: V2V and V2R. In addition, SELWAK maintains secret keys for secure communication between Roadside Units (RSUs). The performance evaluation of SELWAK affirms that it is lightweight in terms of computational cost and communication overhead because SELWAK uses a bitwise Exclusive-OR operation and one-way hash functions. The formal and informal security analysis of SELWAK shows that it is robust against man-in-the-middle attacks, replay attacks, stolen verifier attacks, stolen OBU attacks, untraceability, impersonation attacks, and anonymity. Moreover, a formal security analysis is presented using the Real-or-Random (RoR) model.

Towards the Design of Efficient and Secure Architecture for Software-Defined Vehicular Networks.

Recently, by the rapid development of Vehicular Ad Hoc Networks (VANETs) and the advancement of Software Defined Networking (SDN) as an emerging technology, the Software-Defined Vehicular Network (SDVN) has a tremendous attraction in the academia and research community. SDN's unique properties and features, such as its flexibility, programmability, and centralized control, make the network scalable and straightforward. In VANETs, traffic management and secure communication of vehicle information using the public network are the main research dimensions in the current era for the researchers to be considered while designing an efficient and secure VANETs architecture. This paper highlights the possible identified threat vectors and efficiently resolves the network vulnerabilities to design a novel and secure hierarchic architecture for SDVN. To solve the above problem, we proposed a Public Key Infrastructure-based digital signature model for efficient and secure communication from Vehicle to Vehicle. We also used the public key authority infrastructure for Vehicle to Infrastructure and the three-way handshake method for secure session creation and secure data communication in the SDN controller. The proposed security is validated through the well-known simulation tool AVISPA. Additionally, a formal security model is applied to validate the design hierarchic architecture's fundamental security properties for SDVN in an efficient and desirable way. In a comparative analysis, we prove that our proposed scheme fulfills all the essential security properties compared to other states of the art schemes.

On the Design of Efficient Hierarchic Architecture for Software Defined Vehicular Networks.

Modern vehicles are equipped with various sensors, onboard units, and devices such as Application Unit (AU) that support routing and communication. In VANETs, traffic management and Quality of Service (QoS) are the main research dimensions to be considered while designing VANETs architectures. To cope with the issues of QoS faced by the VANETs, we design an efficient SDN-based architecture where we focus on the QoS of VANETs. In this paper, QoS is achieved by a priority-based scheduling algorithm in which we prioritize traffic flow messages in the safety queue and non-safety queue. In the safety queue, the messages are prioritized based on deadline and size using the New Deadline and Size of data method (NDS) with constrained location and deadline. In contrast, the non-safety queue is prioritized based on First Come First Serve (FCFS) method. For the simulation of our proposed scheduling algorithm, we use a well-known cloud computing framework CloudSim toolkit. The simulation results of safety messages show better performance than non-safety messages in terms of execution time.

An Efficient and Provable Secure Certificate-Based Combined Signature, Encryption and Signcryption Scheme for Internet of Things (IoT) in Mobile Health (M-Health) System.

Mobile health (M-Health) system is the remote form of Wireless Body Area Networks (WBAN), which can be used for collecting patient's health data in real-time with mobile devices, and storing it to the network servers. The data can be accessed by doctors to monitor, diagnosed and treat patients through a variety of techniques and technologies. The main advantage of the M-Health system is the ease of time-independent communication from physically distant places that enhances the quality of healthcare services at a reduced cost. Furthermore, to provide faster access to the treatment of patients, an M-Health system can be integrated with the internet of things (IoT) to offer preventive or proactive healthcare services by connecting devices and persons. However, its equally great drawback lies in transmitting and receiving the health information wirelessly through an open wireless medium that offers different security and privacy violation threats. We aim to address such a deficiency, and thus a new scheme called an efficient and provable secure certificate-based combined signature, encryption and signcryption (CBCSES) scheme, has been proposed in this article. The scheme not only obtains encryption and signcryption but also provides encryption or signature model alone when needed. To show the effectiveness of the proposed scheme, detailed security analyses, i.e. indistinguishable under adaptive chosen-ciphertext attacks (IND-CBCSES-CCA) and unforgeable under adaptive chosen message attacks (EUF-CBCSES-CMA), and the comparisons with relevant existing schemes are carried out. The results obtained authenticate the superiority of our scheme in terms of both computation and communication costs with enhanced security.

Bovine Serum Albumin Protein-Based Liquid Crystal Biosensors for Optical Detection of Toxic Heavy Metals in Water.

A new methodology involving the use of Bovine Serum Albumin (BSA) as a probe and liquid crystal (LC) as a signal reporter for the detection of heavy metal ions in water at neutral pH was developed. BSA acted as a multi-dentate ligand for the detection of multiple metal ions. The LC sensor was fabricated by immobilizing 3 µg mL-1 BSA solution on dimethyloctadecyl-[3-(trimethoxysilyl)propyl]ammonium chloride (DMOAP)-coated glass slides. In the absence of heavy metal ions, a dark optical image was observed, while in their presence, a dark optical image turned to bright. The optical response was characterized by using a polarized optical microscope (POM). The BSA based LC sensor selectively detected toxic metal ions as compared to s block metal ions and ammonium ions in water. Moreover, the limit of detection was found to be very low (i.e., 1 nM) for the developed new biosensor in comparison to reported biosensors.

Densely substituted piperidines as a new class of elastase inhibitors: Synthesis and molecular modeling studies.

Elastase is the only enzyme that has the capability to degrade elastin and collagen, the two proteins essential for skin and bones. The synthesis of some densely substituted piperidines functionalized with the trifluoromethyl group (4a-j) was carried out. The newly prepared compounds were subjected to elastase enzyme inhibitory potential and antioxidant activity assays. Among the series, 4i (IC50 = 0.341 ± 0.001 µM) exhibited the maximum inhibition against elastase. Binding analysis delineated that the fluorine atom of ligand 4i showed hydrogen and hydrophobic bonds with Thr41 and Thr96, with bond distances of 3.84 and 5.631 Å, respectively. The obtained results indicate that these trifluoromethyl functionalized piperidine derivatives could be considered as potential candidates to treat skin disorders.

Titania Laden Liquid Crystal Based Sensor as Photocatalyst.

The present research work elucidates the photocatalytic effect of titania on liquid crystal based sensor used to detect sodium arsenate in water. The titania nanoparticles with an average size of 18-20 nm were synthesized by hydrothermal method and calcined up to 500 °C to obtain pure anatase phase. The catalytic activity of titania nanoparticles was enhanced by surface modification with (3-aminopropyl) trimethoxysilane. The sensing experiment was performed under visible light irradiation while keeping the concentration of substrate, analyte, the thickness of the liquid crystal layer, temperature and pH values constant. In addition, span 80 (a non-ionic surfactant) was used to obtain homeotropic alignment of liquid crystals. The TiO2 nanoparticles gave dark to bright texture within 53 min while the functionalized titania responded in less than 25 min under similar sensing condition. The detection results showed that the functionalized titania nanoparticles possess greater photocatalytic activity under visible light and enhanced the sensing response than unfunctionalized titania nanoparticles.

Cement dust induce stress and attenuates photosynthesis in Arachis hypogaea.

This study was conducted to investigate the changes in leaf physiological parameters to abiotic stress induced by different levels of cement dust. On day 15, Arachis hypogaea L. plants (sowing day was considered as day 0) were divided into six groups, and cement was sprinkled over plants with the help of hand pump, twice a week at T1 (5 g pot-1), T2 (8 g pot-1), T3 (10 g pot-1), T4 (15 g pot-1), T5 (20 g pot-1), and T0/control (0 g pot-1), until fruit maturity. Morphometric parameters such as root and shoot length, leaf area, and seed weight were significantly higher in T0, while the minimum was recorded in T5. Physiological analyses of leaves and roots revealed a remarkable reduction (p < 0.05) in sugar, amino acid, and protein contents, while the concentration of enzymatic antioxidants was increased in cement-treated plants. The concentration of abscisic acid in leaves was significantly higher in treatment groups as compared with control, while gibberellic acid concentration was low. Strikingly, cement dust decreases the level of leaf photosynthetic pigments, reduces stomatal conductance, and adversely affects photosynthesis. Leaf histological analysis revealed confirmatory evidence of stomatal closure, cell damage, reduced cell area, and abridged leaf thickness. Salient features of the present study provide useful evidence to estimate cement dust as a critical abiotic stress factor, which has adverse effects on photosynthesis, leaf anatomical features, stomatal functioning, and productivity. Our work opens new avenues for a deep portfolio of cement-based stress mediating pathophysiology in Arachis hypogaea.

Concentrations, dietary exposure, and human health risk assessment of heavy metals in market vegetables of Peshawar, Pakistan.

The present study was carried out to assess heavy metal concentrations in ready-to-eat vegetables (RTEs) collected from open markets. Samples of RTEs including lettuce, coriander, and carrot were collected from five different local markets of Peshawar, Pakistan including Industrial estate, Board, Agriculture University, Firdos, and Hashtnaghri on four different dates, i.e., 21st March, 04th April, 19th April, and 05th May, 2016. The samples were analyzed through atomic absorption spectrophotometer to see the amount of heavy metals present in them. The elements studied were cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), and lead (Pb). Maximum Cd, Cr, Cu, Ni, and Pb concentrations in samples collected from different markets were 0.68, 5.28, 12.31, 7.61, and 25.04 mg kg-1, respectively, whereas maximum Cd, Cr, Cu, Ni, and Pb concentrations in RTEs collected at different dates were 0.59, 4.08, 14.85, 7.23, and 21.97 mg kg-1, respectively. The mean Cd, Cr, and Pb concentrations exceeded the permissible limits, while Cu and Ni were found within the limits set by FAO/WHO in all studied RTEs. The daily dietary intake and hazard quotient (HQ) showed great variations. The HQ was found > 1 for Pb in all studied vegetables, while it was < 1 for Cd, Cr, Cu, and Ni with few exceptions. It can be concluded from the study that heavy metal concentrations were above the permissible toxicity levels and their continuous consumption may cause several health issues.

Impact assessment of leaf pigments in selected landscape plants exposed to roadside dust.

Continuous addition of undesired effluents to the environment affects foliar surface of leaf, changes their morphology, stomata, photosynthetic pigments, and biochemical constituents which result in massive damage due to persistent nature of the pollutant. In persistent hostile environment, plants fail to grow and develop, and the effects are often extensive. In current study, landscape plants were exposed to different levels of road dust to analyze the effect on various photosynthetic pigments. Dry roadside sediments were collected through a vacuum pump and passed through filters to get fine particles less than 100 µm and sprinkled on Euphorbia milii (EM), Gardenia jasminoides (GJ), and Hibiscus rosa-sinensis (HRs) by using a hand pump, twice daily at T1 (control), T2, T3, and T4 (0, 2, 4, and 6 g/plant, respectively) for a period of 3 months in green house. Road sediment significantly reduces leaf pigments in landscape plants population and the effects were more severe in high level of dust deposition. Individual response of EM, GJ, and HRs to different levels of road dust was variable; however, road sediment significantly reduces leaf pigments at high dose of roadside dust deposition. EM plants exposed to 2 g/plant roadside dust showed higher chlorophyll-a, chlorophyll-b, total chlorophyll, chlorophyllide-b, and polar carotenoid contents as compared to GJ and HRs. Leaf chlorophyll-a, chlorophyll-b, total chlorophyll, carotenoid, and polar carotenoid contents of EM were higher than GJ and HRs in T3 and T4 treatments. However HRs showed significantly higher protochlorophyllide, chlorophyllide-a, and pheophytin-b contents of leaf in T4 group. EM was found as tolerant landscape plant followed by HRs. GJ was most vulnerable to road dust stress. Present study concludes that the entire biosynthesis of leaf pigments is in chain and interlinked together where effect of road dust on one pigment influences other pigments and their derivatives. Salient features of the present study provide useful evidence to estimate roadside dust as a major risk factor for plant pigments, and plants in green belt along roadside suffer retarded growth and fail to establish and develop.

Accumulation of heavy metals in edible parts of vegetables irrigated with waste water and their daily intake to adults and children, District Mardan, Pakistan.

Green vegetable crops irrigated with wastewater are highly contaminated with heavy metals and are the main source of human exposure to the contaminants. In this study accumulation of eight heavy metals (Cu, Ni, Zn, Cr, Fe, Mn, Co and Pb) in green vegetables like Allium cepa, Allium sativum, Solanum lycopersicum and Solanum melongena, irrigated with wastewater in Mardan are studied using Atomic Absorption spectrophotometer. The studied metals in vegetable grown on wastewater irrigated soil were significantly higher than those of tube well water irrigated soil and WHO/FAO permissible limits (P<0.05). The most heavily contaminated vegetable was wastewater irrigated A. cepa, where the accumulation of Mn (28.05 mg kg(-1)) in the edible parts was 50-fold greater than A. cepa irrigated with tube well water irrigated soil. It may be concluded that both adults and children consuming these vegetables grown in wastewater irrigated soil ingest significant amount of these metals and thus can cause serious health problems.